From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] text editor
From: forsyth@caldo.demon.co.uk
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Date: Fri, 26 Apr 2002 12:41:38 +0100
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normally i try to keep out of these discussions.
i've had my fill for three generations, but this
remark caught my attention:

>>pretty much requires visual feedback.  I.e. you need to watch the
>>screen while you are using it.  Which is bloody inconvenient in a lot

now i'm confused: what are you watching when using ijkl (or whatever it is)?
don't you watch the screen for the position of the text cursor, to
decide where to move next, and to see the effect of your changes?

> slower.  It may be counterintuitive, but I believe it has been shown
> by research, not that I can quote anything.  You have to move your
> hands to get to the cursor keys

it was Tognazzi, in an article reprinted in ``Tog on Interfaces'', who noted
that in experiments done by Apple people repeatedly would stoutly maintain
they had completed set tasks much faster using commands and keys even though they
had just been timed to be significantly faster using the mouse.

the interesting bit was the suspected cause.  it wasn't the
hand movements (you might need to do that for both interfaces).
i haven't got the book to hand so i'll give a bad summary.
(To see the correct explanation, buy the book and support ageing interface designers.)
it was something like this: the use of keys+commands
required a higher level of mental planning to organise the interaction,
which apparently obscures the perception of the passage of time--think
of being deeply engaged in something and being surprised when you look at a clock--
whereas the use of the mouse was done at a lower, mechanical level that
left the mind free for higher things, such as complaining about the mouse.
(Tog's article is more interesting and less flippant.)